import { timingSafeEqual } from "node:crypto";

/**
 * Constant-time string comparison. `timingSafeEqual` throws on mismatched
 * buffer lengths, which would itself leak length via which branch throws -
 * so a length mismatch is treated as a plain (also constant-time-irrelevant,
 * since it never reaches the byte comparison) false rather than propagating.
 */
export function timingSafeStringEqual(a: string, b: string): boolean {
  const bufA = Buffer.from(a);
  const bufB = Buffer.from(b);
  if (bufA.length !== bufB.length) return false;
  return timingSafeEqual(bufA, bufB);
}